What is the severity of CVE-2024-20436?

CVE-2024-20436 has a high severity rating due to its potential impact causing denial of service conditions.

How do I fix CVE-2024-20436?

To mitigate CVE-2024-20436, update the Cisco IOS XE Software to a fixed release as outlined in Cisco's security advisory.

Which versions of Cisco IOS XE are affected by CVE-2024-20436?

CVE-2024-20436 affects multiple versions of Cisco IOS XE, including versions 3.9.0as to 17.12.1a.

Is authentication required to exploit CVE-2024-20436?

No, CVE-2024-20436 can be exploited by an unauthenticated remote attacker.

What type of vulnerability is CVE-2024-20436?

CVE-2024-20436 is a denial of service (DoS) vulnerability associated with a null pointer dereference.

Vulnerability/
CVE-2024-20436

high

8.6

CWE

476

25/9/2024

8/10/2024

CVE-2024-20436: Null Pointer Dereference

First published: Wed Sep 25 2024(Updated: 6 months ago)

A vulnerability in the HTTP Server feature of Cisco IOS XE Software when the Telephony Service feature is enabled could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to a null pointer dereference when accessing specific URLs. An attacker could exploit this vulnerability by sending crafted HTTP traffic to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, causing a DoS condition on the affected device.

Credit: ykramarz@cisco.com

Affected Software	Affected Version	How to fix
Cisco IOS XE Software	=3.9.0as
Cisco IOS XE Software	=3.9.1s
Cisco IOS XE Software	=3.9.2s
Cisco IOS XE Software	=3.10.0s
Cisco IOS XE Software	=3.10.1s
Cisco IOS XE Software	=3.10.2s
Cisco IOS XE Software	=3.10.2ts
Cisco IOS XE Software	=3.10.3s
Cisco IOS XE Software	=3.10.4s
Cisco IOS XE Software	=3.10.5s
Cisco IOS XE Software	=3.10.6s
Cisco IOS XE Software	=3.10.7s
Cisco IOS XE Software	=3.10.8as
Cisco IOS XE Software	=3.10.8s
Cisco IOS XE Software	=3.10.9s
Cisco IOS XE Software	=3.10.10s
Cisco IOS XE Software	=3.11.0s
Cisco IOS XE Software	=3.11.1s
Cisco IOS XE Software	=3.11.2s
Cisco IOS XE Software	=3.11.3s
Cisco IOS XE Software	=3.11.4s
Cisco IOS XE Software	=3.12.0s
Cisco IOS XE Software	=3.12.1s
Cisco IOS XE Software	=3.12.2s
Cisco IOS XE Software	=3.12.3s
Cisco IOS XE Software	=3.12.4s
Cisco IOS XE Software	=3.13.0s
Cisco IOS XE Software	=3.13.1s
Cisco IOS XE Software	=3.13.2s
Cisco IOS XE Software	=3.13.3s
Cisco IOS XE Software	=3.13.4s
Cisco IOS XE Software	=3.13.5s
Cisco IOS XE Software	=3.13.6as
Cisco IOS XE Software	=3.13.6s
Cisco IOS XE Software	=3.13.7s
Cisco IOS XE Software	=3.13.8s
Cisco IOS XE Software	=3.13.9s
Cisco IOS XE Software	=3.13.10s
Cisco IOS XE Software	=3.14.0s
Cisco IOS XE Software	=3.14.1s
Cisco IOS XE Software	=3.14.2s
Cisco IOS XE Software	=3.14.3s
Cisco IOS XE Software	=3.14.4s
Cisco IOS XE Software	=3.15.0s
Cisco IOS XE Software	=3.15.1cs
Cisco IOS XE Software	=3.15.1s
Cisco IOS XE Software	=3.15.2s
Cisco IOS XE Software	=3.15.3s
Cisco IOS XE Software	=3.15.4s
Cisco IOS XE Software	=3.16.0cs
Cisco IOS XE Software	=3.16.0s
Cisco IOS XE Software	=3.16.1as
Cisco IOS XE Software	=3.16.2s
Cisco IOS XE Software	=3.16.3s
Cisco IOS XE Software	=3.16.4as
Cisco IOS XE Software	=3.16.4bs
Cisco IOS XE Software	=3.16.4ds
Cisco IOS XE Software	=3.16.5s
Cisco IOS XE Software	=3.16.6bs
Cisco IOS XE Software	=3.16.6s
Cisco IOS XE Software	=3.16.7as
Cisco IOS XE Software	=3.16.7bs
Cisco IOS XE Software	=3.16.7s
Cisco IOS XE Software	=3.16.8s
Cisco IOS XE Software	=3.16.9s
Cisco IOS XE Software	=3.16.10s
Cisco IOS XE Software	=3.17.0s
Cisco IOS XE Software	=3.17.1s
Cisco IOS XE Software	=3.17.2s
Cisco IOS XE Software	=3.17.3s
Cisco IOS XE Software	=3.17.4s
Cisco IOS XE Software	=3.18.2asp
Cisco IOS XE Software	=16.2.1
Cisco IOS XE Software	=16.2.2
Cisco IOS XE Software	=16.3.1
Cisco IOS XE Software	=16.3.1a
Cisco IOS XE Software	=16.3.2
Cisco IOS XE Software	=16.3.3
Cisco IOS XE Software	=16.3.4
Cisco IOS XE Software	=16.3.5
Cisco IOS XE Software	=16.3.6
Cisco IOS XE Software	=16.3.7
Cisco IOS XE Software	=16.3.8
Cisco IOS XE Software	=16.3.9
Cisco IOS XE Software	=16.3.10
Cisco IOS XE Software	=16.3.11
Cisco IOS XE Software	=16.4.1
Cisco IOS XE Software	=16.4.2
Cisco IOS XE Software	=16.4.3
Cisco IOS XE Software	=16.5.1
Cisco IOS XE Software	=16.5.1b
Cisco IOS XE Software	=16.5.2
Cisco IOS XE Software	=16.5.3
Cisco IOS XE Software	=16.6.1
Cisco IOS XE Software	=16.6.2
Cisco IOS XE Software	=16.6.3
Cisco IOS XE Software	=16.6.4
Cisco IOS XE Software	=16.6.5
Cisco IOS XE Software	=16.6.6
Cisco IOS XE Software	=16.6.7
Cisco IOS XE Software	=16.6.8
Cisco IOS XE Software	=16.6.9
Cisco IOS XE Software	=16.6.10
Cisco IOS XE Software	=16.7.1
Cisco IOS XE Software	=16.7.2
Cisco IOS XE Software	=16.7.3
Cisco IOS XE Software	=16.8.1
Cisco IOS XE Software	=16.8.1s
Cisco IOS XE Software	=16.8.2
Cisco IOS XE Software	=16.8.3
Cisco IOS XE Software	=16.9.1
Cisco IOS XE Software	=16.9.1s
Cisco IOS XE Software	=16.9.2
Cisco IOS XE Software	=16.9.3
Cisco IOS XE Software	=16.9.4
Cisco IOS XE Software	=16.9.5
Cisco IOS XE Software	=16.9.6
Cisco IOS XE Software	=16.9.7
Cisco IOS XE Software	=16.9.8
Cisco IOS XE Software	=16.10.1
Cisco IOS XE Software	=16.10.1a
Cisco IOS XE Software	=16.10.1b
Cisco IOS XE Software	=16.10.1e
Cisco IOS XE Software	=16.10.1s
Cisco IOS XE Software	=16.10.2
Cisco IOS XE Software	=16.10.3
Cisco IOS XE Software	=16.11.1
Cisco IOS XE Software	=16.11.1a
Cisco IOS XE Software	=16.11.1b
Cisco IOS XE Software	=16.11.1s
Cisco IOS XE Software	=16.11.2
Cisco IOS XE Software	=16.12.1
Cisco IOS XE Software	=16.12.1a
Cisco IOS XE Software	=16.12.1c
Cisco IOS XE Software	=16.12.1s
Cisco IOS XE Software	=16.12.2
Cisco IOS XE Software	=16.12.2s
Cisco IOS XE Software	=16.12.3
Cisco IOS XE Software	=16.12.3s
Cisco IOS XE Software	=16.12.4
Cisco IOS XE Software	=16.12.4a
Cisco IOS XE Software	=16.12.5
Cisco IOS XE Software	=16.12.6
Cisco IOS XE Software	=16.12.7
Cisco IOS XE Software	=16.12.8
Cisco IOS XE Software	=17.1.1
Cisco IOS XE Software	=17.1.1s
Cisco IOS XE Software	=17.1.1t
Cisco IOS XE Software	=17.1.3
Cisco IOS XE Software	=17.2.1
Cisco IOS XE Software	=17.2.1r
Cisco IOS XE Software	=17.2.1v
Cisco IOS XE Software	=17.2.2
Cisco IOS XE Software	=17.2.3
Cisco IOS XE Software	=17.3.1
Cisco IOS XE Software	=17.3.1a
Cisco IOS XE Software	=17.3.2
Cisco IOS XE Software	=17.3.3
Cisco IOS XE Software	=17.3.4
Cisco IOS XE Software	=17.3.4a
Cisco IOS XE Software	=17.3.5
Cisco IOS XE Software	=17.3.6
Cisco IOS XE Software	=17.3.7
Cisco IOS XE Software	=17.3.8
Cisco IOS XE Software	=17.3.8a
Cisco IOS XE Software	=17.4.1
Cisco IOS XE Software	=17.4.1a
Cisco IOS XE Software	=17.4.1b
Cisco IOS XE Software	=17.4.2
Cisco IOS XE Software	=17.5.1
Cisco IOS XE Software	=17.5.1a
Cisco IOS XE Software	=17.6.1
Cisco IOS XE Software	=17.6.1a
Cisco IOS XE Software	=17.6.2
Cisco IOS XE Software	=17.6.3
Cisco IOS XE Software	=17.6.3a
Cisco IOS XE Software	=17.6.4
Cisco IOS XE Software	=17.6.5
Cisco IOS XE Software	=17.6.5a
Cisco IOS XE Software	=17.6.6
Cisco IOS XE Software	=17.6.6a
Cisco IOS XE Software	=17.7.1
Cisco IOS XE Software	=17.7.1a
Cisco IOS XE Software	=17.7.2
Cisco IOS XE Software	=17.8.1
Cisco IOS XE Software	=17.8.1a
Cisco IOS XE Software	=17.9.1
Cisco IOS XE Software	=17.9.1a
Cisco IOS XE Software	=17.9.2
Cisco IOS XE Software	=17.9.2a
Cisco IOS XE Software	=17.9.3
Cisco IOS XE Software	=17.9.3a
Cisco IOS XE Software	=17.9.4
Cisco IOS XE Software	=17.9.4a
Cisco IOS XE Software	=17.10.1
Cisco IOS XE Software	=17.10.1a
Cisco IOS XE Software	=17.10.1b
Cisco IOS XE Software	=17.11.1
Cisco IOS XE Software	=17.11.1a
Cisco IOS XE Software	=17.12.1
Cisco IOS XE Software	=17.12.1a

Never miss a vulnerability like this again

Reference Links

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-httpsrvr-dos-yOZThut

Frequently Asked Questions

What is the severity of CVE-2024-20436?
CVE-2024-20436 has a high severity rating due to its potential impact causing denial of service conditions.
How do I fix CVE-2024-20436?
To mitigate CVE-2024-20436, update the Cisco IOS XE Software to a fixed release as outlined in Cisco's security advisory.
Which versions of Cisco IOS XE are affected by CVE-2024-20436?
CVE-2024-20436 affects multiple versions of Cisco IOS XE, including versions 3.9.0as to 17.12.1a.
Is authentication required to exploit CVE-2024-20436?
No, CVE-2024-20436 can be exploited by an unauthenticated remote attacker.
What type of vulnerability is CVE-2024-20436?
CVE-2024-20436 is a denial of service (DoS) vulnerability associated with a null pointer dereference.

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